Package ghidra.program.util

Class ContextEvaluatorAdapter

  • All Implemented Interfaces:
    ContextEvaluator
    public class ContextEvaluatorAdapter
extends java.lang.Object
implements ContextEvaluator
    Default behavior implementation of ContextEvaluator passed to SymbolicPropogator Override methods to inspect context.

    • Constructor Detail

      • ContextEvaluatorAdapter

        public ContextEvaluatorAdapter()

    • Method Detail

      • evaluateContextBefore

        public boolean evaluateContextBefore​(VarnodeContext context,
                                     Instruction instr)
        Description copied from interface: ContextEvaluator
        Evaluate the current instruction given the context before the instruction is evaluated
        Specified by:
        evaluateContextBefore in interface ContextEvaluator
        Parameters:
        context - describes current state of registers
        instr - instruction whose context has not yet been applied
        Returns:
        true if evaluation should stop

      • evaluateContext

        public boolean evaluateContext​(VarnodeContext context,
                               Instruction instr)
        Description copied from interface: ContextEvaluator
        Evaluate the current instruction given the final context for the instruction
        Specified by:
        evaluateContext in interface ContextEvaluator
        Parameters:
        context - describes current state of registers
        instr - instruction whose context has been applied
        Returns:
        true if evaluation should stop, false to continue evaluation

      • evaluateConstant

        public Address evaluateConstant​(VarnodeContext context,
                                Instruction instr,
                                int pcodeop,
                                Address constant,
                                int size,
                                RefType refType)
        Description copied from interface: ContextEvaluator
        Evaluate a potential constant to be used as an address or an interesting constant that should have a reference created for it. Computed values that are not know to be used as an address will be passed to this function. For example a value passed to a function, or a stored constant value.
        Specified by:
        evaluateConstant in interface ContextEvaluator
        Parameters:
        context - current program context
        instr - instruction on which this reference was detected
        pcodeop - the PcodeOp operation that is causing this potential constant
        constant - constant value (in constant.getOffset() )
        size - size of constant value in bytes
        refType - reference type (flow, data/read/write)
        Returns:
        the original address unchanged if it should be a reference null if the constant reference should not be created a new address if the value should be a different address or address space Using something like instr.getProgram().getAddressFactory().getDefaultAddressSpace();

      • evaluateReference

        public boolean evaluateReference​(VarnodeContext context,
                                 Instruction instr,
                                 int pcodeop,
                                 Address address,
                                 int size,
                                 RefType refType)
        Description copied from interface: ContextEvaluator
        Evaluate the reference that has been found on this instruction. Computed values that are used as an address will be passed to this function. For example a value passed to a function, or a stored constant value.
        Specified by:
        evaluateReference in interface ContextEvaluator
        Parameters:
        context - current program context
        instr - instruction on which this reference was detected
        pcodeop - the PcodeOp operation that is causing this reference
        address - address being referenced
        size - size of the item being referenced (only non-zero if load or store of data)
        refType - reference type (flow, data/read/write)
        Returns:
        false if the reference should be ignored (or has been taken care of by this routine)

      • evaluateDestination

        public boolean evaluateDestination​(VarnodeContext context,
                                   Instruction instruction)
        Description copied from interface: ContextEvaluator
        Evaluate the instruction for an unknown destination
        Specified by:
        evaluateDestination in interface ContextEvaluator
        Parameters:
        context - current register context
        instruction - instruction that has an unknown destination
        Returns:
        true if the evaluation should stop, false to continue evaluation

      • unknownValue

        public java.lang.Long unknownValue​(VarnodeContext context,
                                   Instruction instruction,
                                   Varnode node)
        Description copied from interface: ContextEvaluator
        Called when a value is needed for a register that is unknown
        Specified by:
        unknownValue in interface ContextEvaluator
        Parameters:
        context - current register context
        instruction - instruction that has an unknown destination
        node - varnode for the register being accessed to obtain a value
        Returns:
        null if the varnode should not have an assumed value. a long value if the varnode such as a Global Register should have an assumed constant

      • followFalseConditionalBranches

        public boolean followFalseConditionalBranches()
        Description copied from interface: ContextEvaluator
        Follow all branches, even if the condition evaluates to false, indicating it shouldn't be followed.
        Specified by:
        followFalseConditionalBranches in interface ContextEvaluator
        Returns:
        true if false evaluated conditional branches should be followed.

      • evaluateSymbolicReference

        public boolean evaluateSymbolicReference​(VarnodeContext context,
                                         Instruction instr,
                                         Address address)
        Description copied from interface: ContextEvaluator
        Evaluate the reference that has been found on this instruction that points into an unknown space that has been designated as tracked.
        Specified by:
        evaluateSymbolicReference in interface ContextEvaluator
        Parameters:
        context - current program context
        instr - instruction on which this reference was detected
        address - address being referenced
        Returns:
        false if the reference should be ignored (or has been taken care of by this routine) true to allow the reference to be created

      • allowAccess

        public boolean allowAccess​(VarnodeContext context,
                           Address addr)
        Description copied from interface: ContextEvaluator
        Evaluate the address and check if the access to the value in the memory location to be read The address is read-only and is not close to this address.
        Specified by:
        allowAccess in interface ContextEvaluator
        Parameters:
        context - current program context
        addr - Address of memory where location is attempting to be read
        Returns:
        true if the access should be allowed